I must admit that I have never read the orignal source material. The concept is very intriguing and I do love the symbiote trope. The twist of Nightshade hosting the runaway mate was a very nice touch. I feel like I'm missing a storyline here though. Is this angling off the comics? Based on Nightshade's thoughts at the end I'd think she was Willow but there were so many references in the Red Witch I decided I must be in error on that front.

Xander as ultimate badass in a believable way, because of the symbiote, was very fun. As was his arriving to save Faith just as she's on the verge of rescuing herself. The lockpick hidden in the arm is a classic! I also really enjoyed how Xander's symbiote seemed pretty happy and Nightshade's seemed to think she'd made a bad deal.

Not your best work but a fun romp.